As of Wednesday, Ducey had about 36% of the vote with an estimated 97% of precincts reporting. Scott Smith, former mayor of Mesa, came in second with 22% of the vote. Four other candidates rounded out the field.

Ducey will face off against Democrat Fred DuVal to succeed Gov. Jan Brewer in the heavily Republican state. DuVal, a White House staffer during the Bill Clinton administration and former chairman with the Arizona Board of Regents, ran unopposed in the primary.

The Tuesday election came a day after the U.S. 10th Circuit Court of Appeals in Denver heard arguments on the constitutionality of laws in Arizona and Kansas requiring residents to prove citizenship through a passport or birth certificate before they can register to vote in state and local elections. The states' rules are stricter than federal law, which requires a voter simply to affirm U.S. citizenship in writing.

As a result, Arizona held a two-tiered primary election. Voters who had not proved their U.S. citizenship to the state’s satisfaction were given separate ballots allowing them to vote for U.S. Congress — not for governor or any other state offices. Those who had proved their citizenship were given a regular ballot with all the races.

Supporters argue that such laws prevent voter fraud. Opponents maintain that the real motivation is to make it more difficult for minorities and the poor to vote.

One day before Arizona’s primary election, the U.S. 10th Circuit Court of Appeals in Denver heard arguments Monday on the constitutionality of voters having to prove citizenship through a passport or birth certificate before they can register to vote.

The controversy over Indiana’s religious freedom law has opened a new — and predictable — divide in the 2016 presidential race, as Republicans rise to its defense and Democrats condemn the legislation as discriminatory against gays and lesbians.

When Indiana approved a law designed to allow residents and business owners to use their religious beliefs as reason to deny services to some people, the conservative state braced for some fallout. But the response was quicker and harder after a campaign from critics who argued the law...

President Obama called the work of the late Sen. Edward M. Kennedy a positive example for a country increasingly weary of politics, saying Monday that he hoped a new institute devoted to Kennedy's work and the Senate he served in could "help plant the seed of noble...

The Supreme Court rejected a free-speech appeal Monday from several California high school students who were told they could not wear a shirt emblazoned with an American flag on the Cinco de Mayo holiday.